8. Use the following terms: interphase, prophase, metaphase, anaphase, telophase, chromosome, spindle fibers, centrioles.

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1 Midterm Exam Study Guide: 2nd Quarter Concepts Cell Division 1. The cell spends the majority of its life in INTERPHASE. This phase is divided up into the G 1, S, and G 2 phases. During this stage, the cell grows, carries out normal function and REPLICATES DNA. 2. Eukaryotic cells reproduce by MITOSIS, the process of nuclear division. This process has four sub- stages including prophase, METAPHASE, anaphase, and _TELOPHASE_. 3. During prophase, the nuclear membrane breaks down and DNA condenses into X shaped structures called_chromosomes_. DuringMETAPHASE_, chromosomes attach to the spindle apparatus and line up along the middle of the cell. Next, chromosomes begin to move towards the poles of the cell during ANAPHASE_. Finally, during telophase chromosomes reach the poles and two new NUCLEI form to surround the chromosomes. 4. The cell cycle ends with CYTOKINESIS, the stage in which two new identical cells form. 5. Mitosis results in the formation of two identical _DIPLOID_cells, meaning that they have a complete set of genetic information contained in chromosomes. 6. Chromosomes are composed of _SISTER chromatids that are held together by a centromere which is the site where the spindle fibers attach to pull the chromosomes apart during mitosis. 7. At times mitosis becomes out of control and may result in _CANCER_as tumors or large masses of cells are produced. 8. Use the following terms: interphase, prophase, metaphase, anaphase, telophase, chromosome, spindle fibers, centrioles. INTERPHASE PROPHASE CENTRIOLES METAPHASE CHROMOSOMES SPINDLE FIBERS TELOPHASE ANAPHASE 9. Draw what the next stage of the cell cycle would show. Next label this stage and explain what the final product of mitosis is. DRAWING SHOULD SHOW TWO NEW SEPERATED CELLS CYTOKINESIS FINAL PRODUCT IS 2 IDENTICAL DIPLOID CELLS.

2 10. MEIOSIS is the process of reduction division in which the number of chromosomes per cell is cut in half through the separation of homologous chromosomes in a diploid cell. This process can be thought of as double mitosis. The cell goes through the regular stages of mitosis but then continues the cycle by reentering PROPHASE a second time. As the cell goes through the remaining stages again, the number of chromosomes is cut in half resulting in 4 _HAPLOID daughter cells that have unique genetic information inside of them. Meiosis produces _SPERM in males and _EGGS_ in females. During fertilization, the sperm and egg join and produce a new, unique, _HAPLOID cell that now has a full set of genetic information. Cells produced during meiosis are unique due to CROSSING- OVER_, the process when chromosomes overlap and genes switch places. Also, millions of sperm are produced by males but only one (usually) fertilized the egg. Women produce 4 eggs, but only one is able to be fertilized. The others are called POLAR BODIES and are discarded by the body. 11. What is the purpose of meiosis? TO CREATE GENETICALLY UNIQUE HAPLOID REPRODUCTIVE CELLS 12. What is the final product of meiosis? 4 HAPLOID CELLS 13. Complete the following chart that compares mitosis and meiosis. Mitosis Meiosis Function Growth; regeneration of new REPRODUCTION cells Location in the body All body cells REPRODUCTIVE ORGANS Number of daughter cells 2 4 Resulting cells diploid or DIPLOID HAPLOID haploid? Number of phases 4 (PMAT) 8 (PMATPMAT) Number of cell divisions 1 2 Difference in DNA between parent and daughter cells? DAUGHTER CELLS HAVE IDENTICAL DNA AS PARENT CELL Chromosomes assort independently, so each daughter cell has a unique set of DNA. 14. How many chromosomes are present in this karyotype? Does this karyotype belong to a healthy baby or one with a genetic disorder? Support your response with evidence from the karyotype. ABNORMAL THREE #21 S 16. Is this baby a male or a female? MALE- XY 17. What is the diploid number of this child? 47

3 Mendelian Genetics 18. Label the diagram above using the following terms: Parental Generation, F 1 Generation, F 2 Generation, F 3 Generation, Hybrids, and Purebreds. 19. Using your knowledge of dominance, explain why all 4 offspring in the F 1 generation turned out to be tall even though one plant from the P generation was short. BECAUSE THE DOMINANT T ALLELE MASKS THE RECESSIVE t ALLELE. 20. Why did one of the plants in the F 3 generation turn out to be short even though both of the plants from the F 2 generation were tall? BECAUSE THEY ARE HOMO. RECESSIVE AND THEREFORE SHOW ONLY THE RECESSIVE PHENOTYPE % TALL, 25% SHORT 22. Complete the following charts for coat pattern in dogs use C to represent alleles. Example: Dogs can have spotted or solid coats Gene COAT PATTERN Alleles SPOTTED OR SOLID Example: In dogs, solid fur is dominant to spotted fur Gene COAT PATTER Alleles SPOTTED OR SOLID Dominant Allele C Recessive Allele c Example: Possible allele combinations for fur color in rabbits Allele combo. Genotype Phenotype CC Homozygous dominant Solid fur Cc Heterozygous Solid fur Cc Homozygous recessive Spotted fur 23. Complete the punnett square below to show the offspring of a homozygous dominant and heterozygous dog.

4 24. Explain the difference between co- dominance and incomplete dominance. CODOMINANCE RESULTS IN A PHENOTYPE THAT SHOWS BOTH TYPES OF THE TRAIT. INCOMPLETE IS A BLENDING OF BOTH TYPES OF THE TRAIT. 25. Does the following diagram illustrate co- dominance or incomplete dominance? INCOMPLETE (RED+WHITE=PINK) 26. Use the punnett square below to show the offspring of a heterozygous individual with a homozygous recessive individual for sickle cell anemia which is a codominant trait. Ss Ss Ss ss 27. What would be the phenotype of the heterozygous individuals? What % of offspring would have some form of sickle cell disease? Some regular and some sickle cells. 50% 28. Analyze the pedigree below does it show a pedigree for a disease that is controlled by a dominant or recessive allele? Use evidence to support your response. RECESSIVE HAS CARRIERS 29. How many generations are in this pedigree? How many females have the genetic disease in this pedigree? How many are carriers? 0 have the disease 3 are carriers Molecular Genetics 31. What do the letters DNA stand for? _DEOXYRIBONUCLEIC ACID 32. Two scientists are given credit for discovering the structure of DNA. What is the name of those two scientists? a. WATSON b. CRICK_

5 33. DNA is a polymer, which means that is made up of many repeating single units (monomers). What are the monomers called? NUCLEOTIDES 34. The backbone of the DNA molecule is made up of two components, what are these? c. PHOSPHATE GROUP d. DEOXYRIBOSE SUGAR 35. There are four different variations of these monomers (four different bases), what are letters that represent these bases? Use the image at the left to complete the following: Circle a nucleotide. Label the sugar and phosphate. Label the bases that are not already labelled 36. Replicate the following strand of DNA by placing the letter of the correct nitrogenous base on the line provided C C A G T A G T T GGTCATCAA 37. Why does DNA need to replicate? SO CELLS FROM MITOSIS ARE GENETICALLY IDENTICAL AND DIPLOID 38. How do base- pairing rules make DNA replication possible? A ALWAYS BONDS WITH T, G ALWAYS WITH C SO ONE HALF OF THE MOLECULE CAN EASILY MATCH UP WITH MISSNIG BASES 39. Who is the base- pairing rule named after? CHARGAFF 40. What is produced during transcription? mrna 41. What would be the base sequence if the following DNA sequence was transcribed into mrna? A C G T A A T C C G T T C A UGCAUUAGGCAAGU

6 42. What is produced during translation? PROTEINS 43. Explain the function of each type of RNA ribosomal, messenger, and transfer. - MESSENGER- DISPOSABLE COPY OF DNA S INFORMATION LEAVES THE NUCLEUS - RIBOSOMAL- SITE OF MAKING PROTEINS - TRANSFER- CARRY AMINO ACIDS TO RIBOSOME TO MATCH UP WITH mrna CODON 44. Complete the chart below to compare and contrast transcription and translation: Original message or instructions in: Transcription Nucleotide sequence in gene in DNA in chromosome MRNA S CODE IS CHANGED TO A Translation SEQUENCE OF AMINO ACIDS TO Molecule which is synthesized MRNA PROTIENS Location where this takes place Nucleus RIBOSOME 45. Complete the following table using the genetic code wheel below: DNA T C T A G A G A T C C G mrna A G A U C U C U A G G C Amino ARGININE SIRINE LEUCINE GLYCINE Acids 46. When a string of amino acids is joined together which macromolecule is created? PROTEINS